Dr. A. Giinther on Australian Tree-frogs. 251 
Regent’s Park, as well as at my own house, I may make the following 
remarks. In general, I was surprised to find a great similarity in their 
habits with those of our common European Tree-frog. They sleep 
during the day, squatting in a corner, generally selecting a place in 
which they are hidden from view, but easily roused on the approach 
of some insect, which they seize with their tongue. When the prey 
is large, or when they have accidentally seized a small piece of wood, 
&c., together with the insect, they use their fore foot to push the in- 
sect into the mouth, or to remove the object which is unfit for food. 
They never enter the water during the summer months, and tried 
to escape from a tank when put into it. They leave their hiding- 
places towards dusk, becoming very lively, apparently less with the 
object of obtaining food (which they can only procure by quietly 
remaining in wait for it) than with that of enjoying themselves ; and 
Pelodryas ceruleus, which is endowed with a voice, indulged every 
evening iu a musical performance. They became more quiet after 
midnight, and at sunrise they had settled down at some resting- 
place, sometimes one individual choosing the same place for several 
consecutive days. They preferred bluebottle flies to every other 
insect, and never touched ants or black beetles. Pelodryas ceruleus 
feeds freely on meal-worms when other food is scarce; but they are 
frequently vomited, and I doubt whether these frogs could be kept 
in good health if restricted to this particular kind of food. In all 
these points the Australian species mentioned agree with the Euro- 
pean Tree-frog, and I need hardly say that they as easily climb 
smooth surfaces, glass, &c., as the latter species. 
Pelodryas ceruleus, White (Giinth. Batr. Sal. pl. 9. fig. B).— 
The natural colour of this species is alight grass-green, which, when 
the animal is kept in the dark or in a very wet place, changes into 
dark sap-green ; roundish yellowish-white spots are sometimes scat- 
tered on the sides. I have mentioned above that it has a voice, which 
is a kind of grunting, somewhat resembling that of Rana esculenta, 
but lower. I must remark, however, that the two examples in the 
menagerie, a male and female, are evidently not full-grown; and I 
was rather surprised to hear a voice at all from the male, as in Hyla 
viridis the vocal sac and the voice are not developed before the indi- 
vidual has attained to maturity and to its full size. The hind limbs 
are comparatively short, and therefore this species cannot make such 
wide jumps as the true Hyle. I could not observe any secretion 
from the parotid glands, which are so much developed in full-sized 
individuals, but which are scarcely perceptible in our specimens. 
These Frogs soon became familiar, especially the male, which, when 
I went to feed them, used to approach and to watch the opening 
through which I introduced the flies into their cage. 
Hyla Peronii, Bibron.—This species is very remarkable on account 
of the change of its colours. When awake, it is brownish olive, 
covered all over with blackish-brown spots, between which small 
green dots are scattered ; the anterior and posterior sides of the thigh 
and the loin are bright yellow, with irregular reticulated black spots. 
The pupil is open, horizontally elliptic, and crossed by a very distinct 
UP is 
